Recurrence of focal segmental glomerular sclerosis (FSGS) after renal transplantation

Long-Term Outcomes of Kidney Transplant Recipients With Primary Idiopathic Focal Segmental Glomerulosclerosis

BACKGROUND

Few data exist on recurrence rates, treatment response, and long-term outcomes in kidney transplant recipients (KTR) with primary focal segmental glomerulosclerosis (FSGS).

METHODS

This retrospective, observational study included 1218 consecutive KTR during 2002 to 2016. All patients with primary idiopathic FSGS were identified through application of strict diagnostic criteria. Outcomes were followed over an average of 70.4 months.

RESULTS

We identified 48 KTR (3.9%) with primary FSGS. Seven-year death-censored graft survival rate was 81% (primary FSGS) versus 85% (control) (P = .297). Eighteen KTR had FSGS recurrence (predicted incidence, 50% after 7 years). Seven-year death-censored graft survival rate in KTR with FSGS recurrence was significantly worse than in FSGS KTR without recurrence (63% versus 96%, P = .010). In the case of FSGS recurrence, a multi-modal treatment approach was applied, including plasma exchange (PE) (100% of patients), intravenous cyclosporine (50%), rituximab (61%), and the "Multiple Target Treatment" (39%). The median number of PE sessions was 27. Proteinuria decreased significantly and persistently during the course of treatment. Complete remission of FSGS was observed in 7 patients (39%); another 7 patients (39%) had partial remission (PE dependence was observed in 4 patients [22%]). Four patients (22%) with FSGS recurrence had early graft loss (<6 months after transplant) despite all treatment efforts.

CONCLUSIONS

In KTR with primary FSGS, a high proportion of recurrence occurred, and recurrence was associated with significantly worse death-censored graft survival rates. However, a multi-modal treatment approach led to improvement of proteinuria and full or partial remission in most patients. Importantly, overall death-censored graft survival rate in KTR with primary FSGS was comparable with that in the control group.

Cryptococcosis as a cause of nephrotic syndrome? A case report and review of the literature

We present a case of a 74 years old male with cutaneous cryptococcosis of the right forearm. Cryptococcus neoformans var. neoformans was cultivated from the skin and from the bloodstream. He was diagnosed with nephrotic syndrome (focal segmental glomerulosclerosis) 21 months prior to admission, which was steroid-dependent. He was treated with prednisone and cyclosporine A. Concurrently with his renal disease he was also diagnosed as having disseminated severe tinea mannum, tinea corporis and tinea cruris; onychomycosis, skin eczema and psoriasis. After a prolonged course of anti-fungal therapy, his skin lesions as well as his nephrotic syndrome recovered completely. Follow up after 7 months without any anti-fungal or immunosuppression showed no skin or renal recurrence. We assume that the renal disease was related to the pre-existing cutaneous cryptococcosis, aggravated by immunosuppression, and discuss the close association between cutaneous cryptococcosis and nephrotic syndrome, as well as similar case reports in the literature.

[Current insights about recurrence of glomerular diseases after renal transplantation]

Recurrence of glomerular disease after renal transplantation is a frequent cause of graft loss. Incidence, risk factors and outcome of recurrence are widely due to the underlying glomerular disease. Graft biopsy analysis is required to confirm the definitive diagnosis of recurrence and to start an appropriate therapy that, in some cases, remains challenging to prevent graft failure. Increased use of protocol biopsy and recent advances in our understanding of the pathogenesis of some glomerular diseases with the identification of some relevant biomarkers provide a unique opportunity to initiate kidney-protective therapy at early stages of recurrence on the graft. This review summarizes our current knowledge on the management of many recurrent primary and secondary glomerulonephritis after kidney transplantation.

Efficacy of the Combination of Immunoadsorption and Rituximab for Treatment in a Case of Severe Focal and Segmental Glomerulosclerosis Recurrence after Renal Transplantation

Background/Aims: We present a case of a male patient with severe recurrence of focal and segmental glomerulosclerosis (FSGS) after transplant. Methods: Before the transplant he was treated with plasma exchange. Massive proteinuria was detected post-transplantation and plasma exchanges were performed without response. We administered 5 doses of Rituximab (375 mg/m2) and partial remission was achieved. Proteinuria relapse occurred 1 year post-transplant, so Immunoadsorption (IA) was started instead of plasma exchange with reduction of proteinuria. Later, 2 new episodes of proteinuria relapse were detected and treated by increasing the number of IA sessions and administering new cycles of Rituximab. After achieving partial remission, IA was reduced to one session every 7–10 days as maintenance therapy. Results: Despite the fact of the severe recurrence, renal function and proteinuria remain stable over 8 years after the transplantation was performed. Conclusion: Combination of maintenance IA and cycles of Rituximab is an effective treatment for aggressive forms of FSGS recurrence after renal transplantation.

Recurrent glomerulonephritis after kidney transplantation: risk factors and allograft outcomes

Recurrent glomerulonephritis after kidney transplantation is a feared complication because it is unpredictable and may have a negative impact on graft outcomes. To better understand this we collected data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry accumulated over 30 years. The incidence, risk factors, and outcomes of recurrent glomerulonephritis in transplant recipients were determined using adjusted Cox proportional hazard and competing risk modeling. A total of 6,597 recipients with biopsy-proven glomerulonephritis as the primary cause of end-stage kidney disease were followed for 51,871 person-years (median duration 7.7 years). The four most common types of glomerulonephritis were IgA nephropathy in 2501 patients, focal segmental glomerulosclerosis (FSGS) in 1403, membranous in 376, and membranoproliferative (MPGN) nephropathy in 357 patients. Among these four types, recurrence was reported in 479 of 4637 patients, and of these, 212 lost their allograft due to recurrence. Older age at transplantation (adjusted hazard ratio [per year increase] 0.96 [95% confidence interval 0.95 - 0.97]) was associated with a lower risk of recurrence. Significantly, the five-year graft survival was 30% for recipients with recurrent MPGN and 57-59% for recipients with FSGS, IgA, and membranous nephropathy. Transplant recipients with recurrent disease were twice as likely to lose their allografts compared to those without recurrence (adjusted hazard ratio 2.04 [1.81-2.31]). Thus, recurrent glomerulonephritis remains a significant cause of graft loss in transplant recipients.

Recurrence of primary glomerulonephritis: Review of the current evidence

In view of the availability of new immunosuppression strategies, the recurrence of allograft glomerulonephritis (GN) are reported to be increasing with time post transplantation. Recent advances in understanding the pathogenesis of the GN recurrent disease provided a better chance to develop new strategies to deal with the GN recurrence. Recurrent GN diseases manifest with a variable course, stubborn behavior, and poor response to therapy. Some types of GN lead to rapid decline of kidney function resulting in a frustrating return to maintenance dialysis. This subgroup of aggressive diseases actually requires intensive efforts to ascertain their pathogenesis so that strategy could be implemented for better allograft survival. Epidemiology of native glomerulonephritis as the cause of end-stage renal failure and subsequent recurrence of individual glomerulonephritis after renal transplantation was evaluated using data from various registries, and pathogenesis of individual glomerulonephritis is discussed. The following review is aimed to define current protocols of the recurrent primary glomerulonephritis therapy.

Renal transplant outcomes in primary FSGS compared with other recipients and risk factors for recurrence: A national review of the Irish Transplant Registry

INTRODUCTION

Primary focal segmental glomerular sclerosis (p-FSGS) is commonly complicated by recurrence (r-FSGS) post-transplantation. Our objective was to describe Irish outcomes for transplantation after end-stage renal disease (ESRD) due to p-FSGS, specifically rates of, and treatments for, r-FSGS.

PATIENTS AND METHODS

Irish patients with biopsy-proven FSGS were identified from the Irish National Kidney Transplant database (1982-2015). Medical record review was performed to identify predictors of r-FSGS and treatments for r-FSGS. Transplant outcomes were compared to outcomes in all renal transplants performed during the same time period using registry data. Demographic and clinical predictors of r-FSGS were identified. Statistical analysis was performed using Stata (version 13, College Station, TX, USA).

RESULTS

Thirty-eight transplant recipients had biopsy-proven p-FSGS, 16 received a second transplant. A total of 3846 transplants formed the comparator group. r-FSGS complicated 60.5% (23/38) of first transplants. Eighty-six percent (10/12) of patients with previous r-FSGS developed recurrent disease after further transplantation. Patients with p-FSGS receiving a first renal transplant had higher rate of graft failure than those with another cause of ESRD (HR 1.9, 95% CI 1.152-3.139). Sixteen patients received immunotherapy for r-FSGS; 12 (86%) had at least partial response, but two (14%) developed significant complications.

DISCUSSION

We demonstrate high rates of r-FSGS and describe modest success from with treatments for r-FSGS.

Plasma exchange in kidney transplantation: Still a valuable option for nephrotic syndrome recurrence

About 30% of the cases of steroid resistant nephrotic syndrome display a genetically determined disease and will not recur after kidney transplant; the other cases with fully or partially immunological pathogenesis display a high risk of post transplant recurrence. Although lots of studies were carried out in the last 50 years the pathogenetic mechanism is still obscure and the therapeutic approach mostly empirical. The cornerstones principles of the therapies are based on removal of a still undefined "permeability factor" through plasma-exchange or other apheresis techniques and inhibition of its synthesis by the immunological system through different drugs. The probability of successfully inducing persistant remission is nowadays around 30%through the different schemes experimented so far which mostly include plasmapheresis. Rituximab in the last years has significantly increased the efficacy of the treatments. Non responders are rapidly evolving to graft loss and will most probably recur also in subsequent transplant. Apart from genetics no other risk factors are predictive for recurrence.

Rituximab for Recurrence of Primary Focal Segmental Glomerulosclerosis After Kidney Transplantation: Clinical Outcomes

BACKGROUND

Rituximab has shown encouraging results for the treatment of kidney transplantation recipients with focal segmental glomerulosclerosis (FSGS) recurrence. However, the correct, opportune, and safe use of rituximab for this indication remains to be determined.

METHODS

This multicenter retrospective study reports on 19 new cases aged 35 (15-66) years who developed FSGS recurrence at 12 (1.5-27) days posttransplantation. Initial treatment consisted of plasma exchanges (PE), high doses of calcineurin inhibitors, and steroids. Rituximab was introduced either immediately (N = 6) or after failure of the initial treatment (N = 10) or failed attempted weaning from PE (N = 3).

RESULTS

Overall, we observed 9 of 19 complete remissions and 3 of 19 partial remissions. Estimated glomerular filtration rates (Modification of Diet in Renal Disease 4) were significantly higher in the responding patients than in nonresponding patients at month (M)12, M36, and M60. Overall, kidney survival at 5 years was 77.4% (95% range, 41.9-92.7). The 5-year graft survival rates in the responding patients and the nonresponding patients were 100% and 36.5%, respectively (P = 0.01). A further course of rituximab was required for 4 patients as a result of FSGS relapse, with good results. During the first year after renal transplantation, 14 patients developed severe infections (16 bacterial, 4 viral, 1 parasitic).

CONCLUSIONS

In kidney transplantation recipients with recurrent FSGS, rituximab therapy may be a recommended treatment for cases that have failed either the initial treatment or weaning from PE.

Optimal management of primary focal segmental glomerulosclerosis in adults

Focal segmental glomerulosclerosis (FSGS) is a frequent glomerular kidney disease that is revealed by proteinuria or even nephrotic syndrome. A diagnosis can be established from a kidney biopsy that shows focal and segmental glomerulosclerosis. This histopathological lesion may be caused by a primary podocyte injury (idiopathic FSGS) but is also associated with other pathologies (secondary FSGS). The first-line treatment for idiopathic FSGS with nephrotic syndrome is a prolonged course of corticosteroids. However, steroid resistance or steroid dependence is frequent, and despite intensified immunosuppressive treatment, FSGS can lead to end-stage renal failure. In addition, in some cases, FSGS can recur on a graft after kidney transplantation: an unidentified circulating factor may be implicated. Understanding of its physiopathology is unclear, and it remains an important challenge for the scientific community to identify a specific diagnostic biomarker and to develop specific therapeutics. This study reviews the treatment of primary FSGS and the recurrence of FSGS after kidney transplantation in adults.

What Can We Do When All Collapses? Fatal Outcome of Collapsing Glomerulopathy and Systemic Lupus Erythematosus With Diffuse Alveolar Hemorrhage: Case Report

INTRODUCTION

Collapsing glomerulopathy (CG) is a rare form of glomerular injury. Although commonly associated with human immunodeficiency virus (HIV) infection, it can occur in association with systemic lupus erythematosus (SLE).

CASE REPORT

We present the case of a 50-year-old man, with chronic kidney disease secondary to focal and segmental glomerulosclerosis, who received a cadaveric kidney transplant in 2007. There were no relevant intercurrences until May 2015, when he presented with nephrotic range proteinuria (± 4 g/d). A graft biopsy was performed and it did not show any significant pathological changes. In September, he developed a full nephrotic syndrome (proteinuria 19 g/d) and a graft biopsy was repeated. CG features were evident with a rich immunofluorescence. Antinuclear antibodies (ANA) and anti-double-stranded DNA (anti-dsDNA) antibodies were positive; the remaining immunologic study was normal. Viral markers for HIV, hepatitis C virus (HCV), and hepatitis B virus (HBV) were negative. The patient was treated with corticosteroid pulses and plasmapheresis (seven treatments). A rapid deterioration of kidney function was seen and he became dialysis dependent. He was discharged with a low-dose immunosuppressive treatment. In October, he was hospitalized with diffuse alveolar hemorrhage (DAH). The auto-immune study was repeated, revealing complement consumption and positive titers of ANA and Anti-dsDNA antibodies. Anti-neutrophil cytoplasmic antibodies (ANCAs) and antiglomerular basement membrane antibody (anti-GBM) were negative. Treatment with intravenous corticosteroids, plasmapheresis, and human immunoglobulin was ineffective and the outcome was fatal.

CONCLUSION

This case report highlights the possible association of CG and SLE. To our knowledge, it is the first case of SLE presenting with CG and DAH, with the singularity of occurring in a kidney transplant recipient receiving immunosuppression.

Unsuccessful Treatment with Abatacept in Recurrent Focal Segmental Glomerulosclerosis after Kidney Transplantation

Recurrence of focal segmental glomerulosclerosis (FSGS) after renal transplantation occurs in up to 20–50% of FSGS patients and is associated with inferior allograft survival. Treatment of both primary FSGS as well as recurrent FSGS after transplantation with plasma exchange and immunosuppression is often unsuccessful and remains a major challenge as the disease still leads to end-stage renal disease and decreased graft survival. Previous case reports have described patients with recurrent FSGS who were successfully treated with a B7-1 inhibitor (abatacept) inducing partial or complete remission. The rational basis for believing in abatacept as a new therapeutic drug for the treatment of FSGS is the study by Yu et al. [N Engl J Med 2013;369: 2416–2423] showing B7-1 in immunostainings of the podocytes. The authors speculated that B7-1 immunostaining of renal biopsies might identify a subgroup of patients who would benefit from abatacept treatment. We present a case with recurrent FSGS after renal transplantation. The patient was unsuccessfully treated with B7-1 inhibitors. Although the patient was treated with abatacept 10 mg/kg body weight twice, the proteinuria and decreased graft function remained unchanged, and he never reached remission.

Hypertension in the Pediatric Kidney Transplant Recipient

Hypertension after kidney transplant is a frequent occurrence in pediatric patients. It is a risk factor for graft loss and contributes to the significant burden of cardiovascular disease (CVD) in this population. The etiology of posttransplant hypertension is multifactorial including donor factors, recipient factors, medications, and lifestyle factors similar to those prevalent in the general population. Ambulatory blood pressure monitoring has emerged as the most reliable method for measuring hypertension in pediatric transplant recipients, and many consider it to be essential in the care of these patients. Recent technological advances including measurement of carotid intima-media thickness, pulse wave velocity, and myocardial strain using specked echocardiography and cardiac magnetic resonance imaging have improved our ability to assess CVD burden. Since hypertension remains underrecognized and inadequately treated, an early diagnosis and an appropriate control should be the focus of therapy to help improve patient and graft survival.

Rituximab is not a "magic drug" in post-transplant recurrence of nephrotic syndrome

Pediatric patients with end-stage renal failure due to severe drug-resistant nephrotic syndrome are at risk of rapid recurrence after renal transplantation. Treatment options include plasmapheresis, high-dose of cyclosporine A/methylprednisolone and more recently-rituximab (anti-B CD20 monoclonal depleting antibody). We report five patients with immediate (1-2 days) post-transplant recurrence of nephrotic syndrome, treated with this kind of combined therapy including 2-4 weekly doses of 375 mg/m(2) of rituximab. Only two (of five) patients have showed full long-term remission, while the partial remission was seen in two cases, and no clinical effect at all was achieved in one patient. The correlation between B CD19 cells depletion and clinical effect was present in two cases only. Severe adverse events were present in two patients, including one fatal rituximab-related acute lung injury.

CONCLUSION

The anti-CD20 monoclonal antibody may be not effective in all pediatric cases of rapid post-transplant recurrence of nephrotic syndrome, and benefit/risk ratio must be carefully balanced on individual basis before taking the decision to use this protocol.

WHAT IS KNOWN

• nephrotic syndrome may recur immediately after renal transplantation • plasmapheresis combined with pharmacotherapy is used as rescue management • rituximab was reported as effective drug both in primary and post-transplant nephrotic syndrome What is New: • rituximab may not be effective is several cases of post-transplant nephrotic syndrome due to variety of underlying mechanisms of the disease, which may be or not be responsive to this drug • there may be no correlation between drug-induced depletion of specific B cells and clinical effect; this might suggest B-cell independent manner of rituximab action.

The role of plasma exchange in treating post-transplant focal segmental glomerulosclerosis: A systematic review and meta-analysis of 77 case-reports and case-series

Background

Evidence on the role of plasma exchange for treating recurrent post-transplant focal segmental glomerulosclerosis (FSGS) comes largely from individual cases and uncontrolled series. We conducted a systematic review and meta-analysis to estimate the remission rate after treatment with plasma exchange, and to determine if remission varied with patient or treatment characteristics.

Methods

We searched MEDLINE, EMBASE, Science Citation Index Expanded, and the Conference Proceedings Citation Index (Science and BIOSIS) for studies of patients with post-transplant recurrent FSGS who were treated with plasma exchange after recurrence (1950–2012). Of 678 studies screened, 77 met our inclusion criteria: 34 case reports (45 patients) and 43 case series (378 patients). We extracted patient-level data from each study and used random-effects models to calculate remission, defined as proteinuria <3.5 g/day (partial) or <0.5 g/day (complete).

Results

The overall remission rate in 423 patients with outcome data was 71 % (95 % CI: 66 % to 75 %). In 235 patients with data on age, remission was similar for adults and children: 69.1 % (95 % CI: 59.6 % to 77.2 %) and 70.2 % (95 % CI: 61.1 % to 77.9 %). Males were more likely to achieve remission (OR = 2.85; 95 % CI: 1.44 to 5.62) and patients treated within 2 weeks of recurrence showed a trend towards higher likelihood of remission (OR = 2.16; 95 % CI: 0.93 to 5.01). Proteinuria >7 g/day at recurrence was inversely associated with remission (OR = 0.43; 95 % CI: 0.19 to 0.97). Age and type of kidney transplant (living vs. deceased) did not associate with remission.

Conclusion

In this systematic review of patients with recurrent post-transplant FSGS, 71 % of patients achieved full or partial remission after treatment with plasma exchange; however, extensive missing data and lack of a control group limit any conclusions on causality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0322-7) contains supplementary material, which is available to authorized users.

Recurrence of Focal and Segmental Glomerulosclerosis After Transplantation

Focal segmental glomerulosclerosis, which is a common glomerular disorder, manifests clinically with a nephrotic syndrome and has a high propensity for recurrence after kidney transplantation. The pathophysiology is currently unknown, and podocytes appear to be the target of one or several circulating factor(s) that lead to the recurrence of proteinuria after kidney transplantation. Identifying these circulating factor(s) and cells involved in its synthesis remains elusive; however, recently, our research on podocyte cytoskeleton biology has opened a new era of treatment. This review will highlight recent progress in the physiopathology of focal segmental glomerulosclerosis recurrence after transplantation and its treatment.

APOL1 Polymorphisms in a Deceased Donor and Early Presentation of Collapsing Glomerulopathy and Focal Segmental Glomerulosclerosis in Two Recipients

Two common polymorphisms in APOL1 (G1 and G2) are conserved in persons of African ancestry, and the presence of two polymorphisms (commonly referred to as risk variants) has been identified as a risk factor for chronic kidney disease and focal seg-mental glomerulosclerosis. In kidney transplantation, deceased donors with two APOL1 risk variants carry an increased risk of renal allograft failure in the recipient. An emerging question is whether these data should influence deceased donor assessment or be used to refine prediction of allograft survival. We present the first detailed report of two cases of recipient glomerular disease in the first year following transplant from a deceased donor later defined as carrying two APOL1 risk variants. A possible "second hit" predisposing to renal disease in these recipients is discussed, one with active cytomegalovirus infection concurrent with collapsing glomerulopathy and renal failure and the other with chronic, slowly healing wound infection and focal segmental glomeru-losclerosis but stable renal function. In retrospect, awareness of the donor APOL1 risk alleles would not have influenced donor selection and ultimately did not influence posttransplant management. These case reports inform further discussion of the value of APOL1 testing for deceased donors.

Acute and Chronic Allograft Dysfunction in Kidney Transplant Recipients

Allograft dysfunction after a kidney transplant is often clinically asymptomatic and is usually detected as an increase in serum creatinine level with corresponding decrease in glomerular filtration rate. The diagnostic evaluation may include blood tests, urinalysis, transplant ultrasonography, radionuclide imaging, and allograft biopsy. Whether it occurs early or later after transplant, allograft dysfunction requires prompt evaluation to determine its cause and subsequent management. Acute rejection, medication toxicity from calcineurin inhibitors, and BK virus nephropathy can occur early or later. Other later causes include transplant glomerulopathy, recurrent glomerulonephritis, and renal artery stenosis.

Recurrence and Treatment after Renal Transplantation in Children with FSGS

Focal segmental glomerulosclerosis (FSGS) is a common cause of end-stage renal disease and a common pathologic diagnosis of idiopathic nephrotic syndrome (NS), especially in steroid-resistant cases. FSGS is known to recur after kidney transplantation, frequently followed by graft loss. However, not all patients with FSGS suffer from recurrence after kidney transplantation, and genetic and secondary FSGS have a negligible risk of recurrence. Furthermore, many cases of recurrence achieve remission with the current management of recurrence (intensive plasmapheresis/immunosuppression, including rituximab), and other promising agents are being evaluated. Therefore, a pathologic diagnosis of FSGS itself should not cause postponement of allograft kidney transplantation. For patients with a high risk of recurrence who presented with classical symptoms of NS, that is, severe edema, proteinuria, and hypoalbuminemia, close monitoring of proteinuria is necessary, followed by immediate, intensive treatment for recurrence.

FSGS Recurrence in Adults after Renal Transplantation

Recurrence of focal segmental glomerulosclerosis (FSGS) in the allograft occurs in 30–50% of patients, and it is associated with poor renal allograft survival. Major risk factors for recurrence are younger age at diagnosis, rapid progression to end-stage renal disease, white race, and the loss of previous allografts due to recurrence. Recent data support the hypothesis that circulating permeability factors play a crucial role in podocyte injury and progression of FSGS. Due to lack of controlled trials, the management of recurrent FSGS is inconsistent and highly empirical. Prophylactic and perioperative treatment with plasmapheresis and high-dose (intravenous) cyclosporine represent the main cornerstones of immunosuppressive therapy. In recent years, therapy with rituximab has shown promising results. Despite evidence of activation of the renin-angiotensin system (RAS) in recurrent FSGS and its association with progression, only limited data exist on the renoprotective role of RAS blockade in this setting. Further well designed studies are needed on pathogenesis risk factors and therapeutical options in FSGS and its recurrence after transplantation.

Update on the treatment of focal segmental glomerulosclerosis in renal transplantation

Focal segmental glomerulosclerosis (FSGS) represents one of the most severe glomerular diseases, with frequent progression to end-stage renal disease and a high rate of recurrence in renal allografts (30%-50%). Recurrent FSGS portends a negative outcome, with the hazard ratio of graft failure being two-fold higher then that of other glomerulonephritis. Two patterns of clinical presentations are observed: Early recurrence, which is characterized by massive proteinuria within hours to days after implantation of the renal graft, and late recurrence, which occurs several months or years after the transplantation. Many clinical conditions have been recognized as risk factors for recurrence, including younger age, rapid progression of the disease to end-stage renal disease on native kidneys, and loss of previous renal allografts due to recurrence. However, much less is known about the incidence and risk factors of the so-called “de novo” type of FSGS, for which sufferers are transplanted patients without disease on native kidneys; but, rapid development of allograft failure is frequently observed. Management of both forms is challenging, and none of the approaches proposed to date have been demonstrated as consistently beneficial or effective. In the present review we report an update on the available therapeutic strategies for FSGS in renal transplantation within the context of a critical overview of the current literature.

Successful Treatment of Focal Segmental Glomerulosclerosis after Kidney Transplantation with Plasma Exchange and Abatacept in a Patient with Juvenile Rheumatoid Arthritis

Recurrent focal segmental glomerulosclerosis (FSGS) after renal transplantation is difficult to treat. Recently a series of four patients unresponsive to plasma exchange (PE) and rituximab, who were successfully treated with abatacept, has been reported. We present a 26-year-old Caucasian patient who suffered from juvenile rheumatoid arthritis and developed severe proteinuria eleven days after transplantation. An allograft biopsy was suggestive of recurrent focal segmental glomerulosclerosis. He did not respond to PE therapy. A first dose of abatacept produced partial remission. Four weeks later proteinuria again increased and a second biopsy showed progression of disease. After another ineffective course of PE he was given a second dose of abatacept, which was followed by rapid, complete, and sustained resolution of proteinuria. This treatment caused a significant increase in BK and JC viremia. Whether abatacept ameliorated proteinuria via an effect on podocytes or on the patient's primary disease remains speculative.

Podocyte directed therapy of nephrotic syndrome-can we bring the inside out?

Several of the drugs currently used for the treatment of glomerular diseases are prescribed for their immunotherapeutic or anti-inflammatory properties, based on the current understanding that glomerular diseases are mediated by immune responses. In recent years our understanding of podocytic signalling pathways and the crucial role of genetic predispositions in the pathology of glomerular diseases has broadened. Delineation of those signalling pathways supports the hypothesis that several of the medications and immunosuppressive agents used to treat glomerular diseases directly target glomerular podocytes. Several central downstream signalling pathways merge into regulatory pathways of the podocytic actin cytoskeleton and its connection to the slit diaphragm. The slit diaphragm and the cytoskeleton of the foot process represent a functional unit. A breakdown of the cytoskeletal backbone of the foot processes leads to internalization of slit diaphragm molecules, and internalization of slit diaphragm components in turn negatively affects cytoskeletal signalling pathways. Podocytes display a remarkable ability to recover from complete effacement and to re-form interdigitating foot processes and intact slit diaphragms after pharmacological intervention. This ability indicates an active inside-out signalling machinery which stabilizes integrin complex formations and triggers the recycling of slit diaphragm molecules from intracellular compartments to the cell surface. In this review we summarize current evidence from patient studies and model organisms on the direct impact of immunosuppressive and supportive drugs on podocyte signalling pathways. We highlight new therapeutic targets that may open novel opportunities to enhance and stabilize inside-out pathways in podocytes.

Focal segmental glomerular sclerosis recurrence with massive proteinuria and anuria immediately after kidney transplantation

Here, we report a case of focal segmental glomerular sclerosis (FSGS) recurrence immediately (47 minutes) after transplantation. A 1-hour biopsy specimen showed large periodic acid-Schiff-positive granules within the cells of the swollen proximal tubule, while electron microscopy revealed podocyte swelling and partial foot process effacement. These findings were worse on day 2 biopsy. Massive proteinuria and anuria were then observed. Two courses (2 × 2 times) of plasmapheresis and rituximab were administered, and the graft function gradually recovered. A day 22 biopsy specimen showed improvement in findings compared to those observed on day 2. One year after transplantation, no signs of FSGS recurrence are evident, and graft function remains good.

Galactose therapy reduces proteinuria in patients with recurrent focal segmental glomerulosclerosis after kidney transplantation

Primary focal segmental glomerulosclerosis is an important cause of end-stage kidney disease with a high rate of recurrent disease after kidney transplantation. Current therapy achieves remission in only half of patients. Recent interest has focused on the potential role of galactose in binding and inactivating the putative circulating permeability factor, supported by in vitro and clinical case report studies. Orally active and without major adverse effects, galactose has a favourable treatment profile compared with current immunosuppressive treatment options. We describe our experience using galactose therapy in two patients with recurrent focal segmental glomerulosclerosis after renal transplantation. Galactose was associated with symptomatic improvement and stabilization of graft function in one case; the other case was complicated by concurrent malignancy. In both cases, we observed a marked reduction in proteinuria with galactose treatment.

Plasma Exchange for the Recurrence of Primary Focal Segmental Glomerulosclerosis in Adult Renal Transplant Recipients: A Meta-Analysis

Background. Posttransplant recurrence of primary focal segmental glomerulosclerosis (rFSGS) in the form of massive proteinuria is not uncommon and has detrimental consequences on renal allograft survival. A putative circulating permeability factor has been implicated in the pathogenesis leading to widespread use of plasma exchange (PLEX). We reviewed published studies to assess the role of PLEX on treatment of rFSGS in adults. Methods. Eligible manuscripts compared PLEX or variants with conventional care for inducing proteinuria remission (PR) in rFSGS and were identified through MEDLINE and reference lists. Data were abstracted in parallel by two reviewers. Results. We detected 6 nonrandomized studies with 117 cases enrolled. In a random effects model, the pooled risk ratio for the composite endpoint of partial or complete PR was 0,38 in favour of PLEX (95% CI: 0,23–0,61). No statistical heterogeneity was observed among included studies (I² = 0%, p = 0,42). On average, 9–26 PLEX sessions were performed to achieve PR. Renal allograft loss due to recurrence was lower (range: 0%–67%) in patients treated with PLEX. Conclusion. Notwithstanding the inherent limitations of small, observational trials, PLEX appears to be effective for PR in rFSGS. Additional research is needed to further elucidate its optimal use and impact on long-term allograft survival.

Recurrent focal segmental glomerulosclerosis after kidney transplantation

Focal segmental glomerulosclerosis (FSGS) is an important cause of glomerular disease in children and adolescents and nearly 50 % of affected patients will progress to end-stage kidney disease over a 5 to 10-year period. Unfortunately, there is no established treatment for disease in the native kidney. Moreover, up to 55 % of patients develop recurrent disease after receiving a kidney transplant, with a substantially higher risk in patients who have already experienced recurrent disease in a prior transplant. A number of clinical and laboratory factors have been identified as risk factors for this complication. In addition, new investigations into podocyte biology and circulating permeability factors have shed light on the cause of recurrent the disease. While a number of novel therapeutic agents have been applied in the management of this problem, there still is no proven treatment. In this review, we summarize recent advances in the epidemiology, pathophysiology, and treatment of recurrent FSGS in pediatric patients who have received a kidney transplant.

A case of recurrent focal segmental glomerulosclerosis after kidney transplantation associated with variant conversion in the Columbia classification

Focal segmental glomerulosclerosis commonly recurs following kidney transplantation. A 33-year-old man underwent living donor kidney transplantation. Proteinuria appeared two months after transplantation, and an episode biopsy on postoperative day 66 revealed recurrent focal segmental glomerulosclerosis lesions of the cellular variant by Columbia classification. We reviewed the native kidney biopsy and confirmed collapsing variant focal segmental glomerulosclerosis. Plasma exchange therapy was performed, and his proteinuria temporarily resolved. A second allograft biopsy performed on postoperative day 200 showed no evidence of focal segmental glomerurosclerosis. He experienced incomplete remission with a proteinuria of 0.5 g/day during the subsequent three years until his urinary protein level rose to 1.3 g/day. A third biopsy performed on postoperative day 1248 showed focal segmental glomerulosclerosis cellular variant lesions. Plasma exchange was resumed in combination with additional rituximab, but his proteinuria persisted. Intermittent plasma exchange was performed 42 times in total. However, his proteinuria continued, and his renal function gradually worsened. A fourth biopsy performed on postoperative day 2540 showed focal segmental glomerulosclerosis collapsing variant lesions with severe interstitial fibrosis and tubular atrophy. He ultimately required hemodialysis seven years after transplantation. Intensive therapy with long-term intermittent plasma exchange and rituximab suppressed proteinuria and preserved graft function for seven years, at which time graft failure occurred. We here present the clinical course and histological findings from consecutive allograft biopsies.

Management of proteinuria in the transplanted patient

Proteinuria is a relatively frequent complication in children after renal transplantation (40-80 %). It is usually mild and non-nephrotic in nature and predominantly tubular in origin. The major causes of post-transplant proteinuria are recurrence of primary glomerulonephritis [mostly focal segmental glomerulosclerosis (FSGS)], rejection (acute and chronic), mTOR inhibitors or hypertension. Proteinuria is a risk factor for graft loss and patient death in adults, and even a mild proteinuria (0.1-0.2 g/day) is associated with impaired graft and patient survival. In children, proteinuria seems to be associated with graft but not patient survival. Proteinuria (protein/creatinine ratio) should be assessed regularly in all children. In children with prior chronic kidney disease due to idiopathic FSGS, proteinuria should be assessed daily during the first month after transplantation to enable early diagnosis of recurrence. The cause of proteinuria should be identified, and graft biopsy should be considered in children with unexplained proteinuria, especially with new onset proteinuria or deterioration of previously mild proteinuria. Treatment must be primarily targeted at the cause of proteinuria, and in normotensive children symptomatic antiproteinuric therapy with angiotensin-converting enzyme inhibitors/angiotensin II receptor antagonists should also be initiated. Other antihypertensive drugs should be used to achieve target blood pressure of <75th percentile. Target proteinuria should be <20 mg/mmol creatinine.

The integrin adhesome: from genes and proteins to human disease

The adhesive interactions of cells with their environment through the integrin family of transmembrane receptors have key roles in regulating multiple aspects of cellular physiology, including cell proliferation, viability, differentiation and migration. Consequently, failure to establish functional cell adhesions, and thus the assembly of associated cytoplasmic scaffolding and signalling networks, can have severe pathological effects. The roles of specific constituents of integrin-mediated adhesions, which are collectively known as the 'integrin adhesome', in diverse pathological states are becoming clear. Indeed, the prominence of mutations in specific adhesome molecules in various human diseases is now appreciated, and experimental as well as in silico approaches provide insights into the molecular mechanisms underlying these pathological conditions.

B cell suppression in primary glomerular disease

Membranous nephropathy, focal segmental glomerulosclerosis (FSGS), and minimal change disease (MCD) are the most common causes of idiopathic nephrotic syndrome. For many years prednisone, alkylating agents, and calcineurin inhibitors have been the standard of therapy for these patients. More effective or better tolerated treatment modalities are needed. B cell targeted therapy was recently introduced in clinical practice. In this review, we briefly summarize the current standard therapy and discuss the efficacy of B cell targeted therapy in primary glomerular diseases. Observational, short-term studies suggest that rituximab is effective and comparable to standard therapy in maintaining remissions in patients with frequently relapsing or steroid-dependent MCD or FSGS. In contrast, response is limited in patients with steroid-resistant nephrotic syndrome. Rituximab also induces remissions in patients with membranous nephropathy. Controlled clinical trials on kidney endpoints are urgently needed to position B cell targeted therapy in clinical practice.

Success with plasmapheresis treatment for recurrent focal segmental glomerulosclerosis in pediatric renal transplant recipients

FSGS recurs in approximately 30% of transplanted kidneys and may lead to graft loss. We retrospectively examined the efficacy of early and intensive PP without additional IS in pediatric kidney transplant patients with recurrent FSGS at our center. Seven of 24 patients (29%) had nephrotic proteinuria and histologic evidence of FSGS recurrence within 1-5 days post-transplantation. PP was initiated early after transplantation and initially performed daily until sustained decline in proteinuria. PP frequency was then individually tapered according to proteinuria. Recurrent FSGS in all seven patients responded to a four- to 32-wk course of PP. Two of seven patients had a second recurrence of FSGS, and both recurrences remitted after an additional 3-6 wk of PP. Median observation period was 4.5 yr (0.8-16.3 yr). Complete remission of recurrent FSGS has been sustained in all seven patients, and all patients have stable graft function with recent plasma creatinine <1.5 mg/dL in six of seven patients. Most recent urine protein/creatinine is 0.13-0.61 mg/mg in six of seven patients. One patient has heavy proteinuria secondary to chronic allograft nephropathy 16 yr post-transplant. Intensive and prolonged PP, when initiated early in the post-operative period, is effective in treating recurrent FSGS and preventing graft loss without the use of additional immunosuppressants.

Early posttransplant nephrotic range proteinuria as a presenting feature of minimal change disease and acute T cell-mediated rejection

Early-onset nephrotic range proteinuria is an extremely rare presentation of an acute rejection episode. Herein, we have reported a patient who developed nephrotic range proteinuria 7 days after receiving a renal allograft from his sister despite minor changes in serum creatinine levels. A kidney biopsy spcimen revealed a T cell-mediated acute rejection process concomitant with minimal change disease (MCD). Proteinuria and renal dysfunction improved dramatically in response to corticosteroids. The possibility of acute cellular rejection and coexisting MCD should be considered in patients with early posttransplantation nephrosis and normal serum creatinine levels. The coexistence of these entities provides support for the role of T cells in the pathogenesis of MCD.

Focal segmental glomerulosclerosis in children: multivariate analysis indicates that donor type does not alter recurrence risk

BACKGROUND

Focal segmental glomerulosclerosis (FSGS), the second leading cause of end stage renal disease in children, appears to be increasing. Moreover, posttransplantation FSGS recurrence is a major problem, and there is concern that children receiving kidneys from living donors (LD) have increased recurrence risk.

METHODS

Data from the United Network for Organ Sharing from 1988 to 2008 were analyzed for number of de novo transplant recipients with a primary diagnosis of FSGS in children 1 to 20 years of age. Poisson regression was used for trend analysis. Univariate and multivariable logistic regression analyses were performed to examine the association of gender, race, human leukocyte antigen matching, age, and donor type with recurrence.

RESULTS

Trend analysis of kidney transplantations for FSGS in children (n=2157) showed an increase in cases of 5.8% per year or 209% over 20 years (P<0.0001). Recurrence was reported in 327 (15%) cases overall, with a preponderance for white recipients (P<0.001) in younger age subgroups (P<0.01). Donor type was significant (P=0.02), with recurrence reported in 17% versus 14% of recipients of kidneys from LDs versus deceased donors. Using multivariate analysis, recipients' young age (P=0.02) and white race (P<0.001) were identified as significant risk factors for recurrence, whereas receiving a LD kidney became insignificant.

CONCLUSIONS

FSGS as a cause of pediatric end-stage renal disease leading to transplantation is on the rise. FSGS recurrence is highest in young, white children, whereas receiving a LD kidney is not independently associated with increased risk of recurrence.

Primary focal and segmental glomerulosclerosis and soluble factor urokinase-type plasminogen activator receptor

Primary focal and segmental glomerulosclerosis (FSGS) may be due to genetic or acquired etiologies and is a common cause of nephrotic syndrome with high morbidity that often leads to end-stage renal failure. The different available therapeutic approaches are unsuccessful, in part due to partially deciphered heterogeneous and complex pathophysiological mechanisms. Moreover, the term FSGS, even in its primary form, comprises a histological description shared by a number of different causes with completely different molecular pathways of disease. This review focuses on the latest developments regarding the pathophysiology of primary acquired FSGS caused by soluble factor urokinase type plasminogen activator receptor, a circulating permeability factor involved in proteinuria and edema formation, and describes recent advances with potential success in therapy.

Glomerular disease recurrence in the renal allograft: a hurdle but not a barrier for successful kidney transplantation

Almost all forms of primary as well as secondary glomerulonephritides may recur after renal transplantation. Recurrence of the original disease is now the third most common cause of late allograft loss. Nevertheless, in most cases it is difficult to assess the true impact of primary disease recurrence in the allograft; histological recurrence with mild features does not necessarily implicate clinically severe disease. Moreover it is often difficult to distinguish recurrent from de novo disease as in membranous glomerulopathy. Because recurrence occurs late, histological lesions of recurrent glomerulonephritis may be unmasked by chronic damage from other causes such as chronic rejection. Beside the difficulties to interpret renal histology due to the variety of allograft lesions, there are no well-established options to prevent clinically severe disease recurrence nor the therapeutic approaches to the problem. The purpose of this review was mainly to underline that almost all primary and secondary glomerulonephritides represent a contraindication to transplantation. For the majority of patients with end-stage renal disease due to glomerulonephritis, transplantation still represents the treatment of choice.

Recurrence of glomerulonephritis after renal transplantation

Recurrence of glomerulonephritis following renal transplantation is considered an important cause of allograft failure. The incidence of recurrence of glomerulonephritis varies widely depending on the definition of recurrence (pathologic recurrence or clinicopathologic recurrence) and the original glomerular disease. Moreover the impact of recurrence of glomerular disease on allograft outcome varies widely between different forms of glomerulonephritis. Whereas IgA nephritis recurs in up to one third of transplanted patients, this is not associated with adverse effects on graft survival. In contrast, recurrent focal segmental glomerulosclerosis and membranoproliferative glomerulopathy have an unfavorable prognosis. Overall, long-term graft survival in patients transplanted for glomerulonephritis is comparable to survival in patients with other causes of ESRD. In recent years, several mechanisms for recurrent disease after transplantation (e.g. PLA2R antibodies in membranous nephropathy and suPAR in FSGS) have been identified, and these findings have helped to elucidate the pathogenesis of glomerular diseases. Although renal transplantation is the treatment of choice for end-stage renal disease as a consequence of glomerulonephritis, further studies are required to develop optimal strategies to prevent, diagnose and treat recurrent glomerular diseases.

Current and emerging treatments for idiopathic focal and segmental glomerulosclerosis in adults

Idiopathic focal and segmental glomerular sclerosis is a frequent cause of nephrotic syndrome and end-stage renal disease. The pathogenesis is still unknown, although the body of evidence suggests that focal and segmental glomerular sclerosis is caused by a not clearly identified circulating factor that alters the permselectivity of the glomerular barrier. Proteinuria is followed by podocyte injury. Glucocorticoids, calcineurin inhibitors, cytotoxic agents and mycophenolate mofetil, either given alone or in combination, may obtain complete or partial remission of proteinuria in 50-60% of patients and protect them from end-stage renal disease, but the remaining patients are resistant to the available drugs. A number of new drugs, including rituximab, galactose and antifibrotic agents, are under investigation.